Circuit Description
The fuel pump is an in-tank type mounted to a fuel sender assembly. The fuel pump will remain on as long as the engine is cranking or running and the Engine Control Module (ECM) is receiving reference pulses from the Crankshaft Position (CKP) sensor. If there are no reference pulses, the ECM will turn OFF the fuel pump 2 seconds after the ignition switch is turned ON or 2 seconds after the engine stops running. The fuel pump delivers fuel to the fuel rail and the fuel injectors, where the fuel system pressure is controlled to 310 kPa (45 psi) by the fuel pressure regulator. The excess fuel is returned to the fuel tank.